Development and validation of a safe communication protocol compliant to railway standards

Journal of the Brazilian Computer Society

Andrea Ceccarelli¹  Duccio Bertieri¹  Andrea Bondavalli¹  Tommaso Zoppi¹  Innocenzo Mungiello²  Mario Barbareschi² 

[1] Department of Mathematics and Informatics, University of Florence, Viale Morgagni 65, 50134, Florence, Italy;Research and Development, Rete Ferroviaria Italiana, Via Curzio Malaparte 8, 50145, Florence, Italy;

关键词: Railway;    Communication protocol;    Safety;    Security;    Safety integrity level;    Verification and validation;    CENELEC;   

DOI  :  10.1186/s13173-021-00106-w

来源: Springer

【 摘 要 】

Railway systems are composed of a multitude of subsystems, sensors, and actuators that exchange datagrams through safety-critical communication protocols. However, the vast majority of these protocols rely on ad hoc interlacing mechanisms and safety codes which raise the heterogeneity and complexity of the overarching railway system. Therefore, Rete Ferroviaria Italiana, the company who is in charge of managing the Italian railway network, coordinated the definition of the Protocollo Vitale Standard (Standard Vital Protocol). This protocol is inspired to, and compliant with, the communication protocols adopted for the European Train Control System (ETCS) (SUBSET, UNISIG, 037, Euroradio FIS, version 2.3. 0; SUBSET, UNISIG, 098, RBC-RBC safe communication interface, 2007), and it is meant to become the standard layer to enable safe communication between components of the Italian railway system. This paper reports our experience in the design, implementation, verification, and validation of the Protocollo Vitale Standard in compliance with the European safety standards for railway systems. We first defined a safety plan and a verification and validation plan, which guide the design, development, verification, and validation activities as required by safety standards. Guidelines of such plans have been followed strictly until completion of the work, which concludes with the provision of a safety case where all safety evidences are summarized. Noticeably, we (i) selected appropriate safety mechanisms, (ii) verified the software design, (iii) implemented the software in compliance with code metrics and coding rules, (iv) conducted tests to validate the protocol against its functional and performance requirements, and ultimately (v) devised all relevant documentation and a safety case which summarizes the evidences needed for certification.

【 授权许可】

CC BY